How to damp proof and level asbestos tiled floor ready to lay laminate

Discussion in 'Subfloor Preparation' started by DIYNovice, Feb 9, 2017.

  1. DIYNovice

    DIYNovice Member

    6
    0
    1
    Hello,

    I'm hoping someone can give me some experienced advice. I am out of my depth!

    My partner and I are planning to lay new laminate flooring over an old asbestos tiled living room floor. My original plan was to get the old tiles completely removed, paint on a DPM and then use a levelling screed before laying fibreboard underlay. Several people told me it was a waste of money though - even the asbestos removal company said it's fine to leave them and lay new flooring over the top rather than spend £s getting them to remove them.

    I haven't done a damp proof test but the outside edge of the floor had a faint whiff of mould when I was taking up the grippers and the underlay had some large stains on it which looked like they may have been caused by damp. I'm assuming then it's not already damp proof.

    I've removed the old carpet, underlay & grippers and cleaned the tiles, removing any broken pieces. The vast majority of the tiles are in good condition, but they are cracked and broken around the edge of the room where the old carpet grippers were nailed into them. The cement floor underneath is showing through in patches (including one fairly large patch where there are no tiles for some reason). I couldn't easily remove all of the broken pieces because they are partly under the skirting board. In the interests of not disturbing them unnecessarily, I have just removed what I can and then mopped the whole floor.

    My problem now is how I adequately seal / damp proof the floor and level it ready for the underlay to go on. I'm not sure what products are safe to use on asbestos tiles, nor which order to do things in - do i level it and then damp proof the lot, or paint on DPM, then level?? I would be painting onto broken tiles so just want to be sure I use something appropriate for that. I asked at B&Q and they didn't know. I looked at garage floor sealants, tile sealants, etc - nothing looks quite appropriate.

    The laminate is also being laid in the understair cupboard, which has part bitumen concrete floor and part something else which i can't identify - looks like home-mixed something has been used to fill in half the floor... I will need to damp proof & level the entire space, not just the tiled part.

    It's Thursday today and my brother is coming on Monday to lay the new floor... Have I run out of time?? Please help!! :(
     
  2. Spacey

    Spacey Super Moderator Staff Member

    6,516
    1,878
    113
    If the tiles are solid enough put a smothING compound over it first to encapsulate them Then you can use a dpm over the top
    But it's not as straight forward as that You still need to know the correct products to use There's different types of dpm and leveling compounds with different uses.
    First...

    When was your property built ?
    Have you had a Professional look at it ?
    Have you had the tiles tested ?
     
  3. DIYNovice

    DIYNovice Member

    6
    0
    1
    Built in the 70s. Professional hasn't seen the floor as it is - i.e. with the carpet removed - but the tiles have been tested and do contain asbestos.

    My brother (who is NOT a professional - just a skilled DIYer) just suggested I use Bostik flexible damp-proofer and waterproofer, painting it directly over the tiles and any exposed concrete.
     
  4. DIYNovice

    DIYNovice Member

    6
    0
    1
    I am guessing about the date it was built - i'd need to check the paperwork that came with the house. Our neighbour says his was built in the 70s so i assume ours is the same. I know DPCs were mandatory after 1965 but I've heard more than once that nevertheless they weren't always installed or at least can become damaged and ineffective.
     
  5. DIYNovice

    DIYNovice Member

    6
    0
    1
    Thank you for your advice. I'm new to this and didn't select reply before. Just to be sure you've seen my previous messages: I think the house was built in the 70s but may have been 60s; the tiles have been tested; we haven't had a professional look at the floor with the carpet etc removed but have had advice on "if the tiles are generally in good condition".

    I've just come across one website which gives advice on covering asbestos tiles that suggest using a pour-on leveling compound (concrete mix) directly over the tiles - sounds similar to what you suggest above. Is self-levelling screed the same sort of thing? Would I then apply DPM over the top of that?

    Thanks so much for your help with this.
     
  6. Spacey

    Spacey Super Moderator Staff Member

    6,516
    1,878
    113
    With those dates more than likely theres no dpm under the concrete slab.

    Yes I'm talking about the same thing
    You need to use Ardex NA leveling compound/screed over the tiles Then Ardex 1c liquid dpm over that once it's dry/next day.
    Or you could use a visqueen sheet dpm
    It's up to you but I'd do the later.

    Good luck with that but I'd advise you get a pro in to get the job done right.

    It could get messy :confused:
     
  7. DIYNovice

    DIYNovice Member

    6
    0
    1
    You would use a visqueen sheet rather than liquid DPM?

    I need products I can buy in store today or tomorrow as I don't have time for online shipping now it's the weekend - need it available to prep the floor on Sunday ideally... is it imperative that I use a latex-based compound? I'm struggling to find one that doesn't need to be ordered online.

    I have confidence my brother can do it - he's done a few laminate floors recently, all look great and fully damp-proofed. I have requested he help with this bit too, as it sounds like it's beyond my skill level!

    Thanks again - feeling much more in control now! :)
     
  8. DIYNovice

    DIYNovice Member

    6
    0
    1
    I just spoke to our asbestos guy again and he's put my mind at rest. He said latex is best but screed is ok, just messier and harder to work with. We might attempt taking all the times up in the end (with appropriate protective overalls & masks) just in the interests of future house value.

    Thank you for your sound advice Spacey - really appreciate it. My head was spinning with the fear factor of asbestos dangers and being a DIY-dunce! Certainly will have learned a thing or two once this is all done! :)
     
  9. pf flooring

    pf flooring Well-Known Member

    1,600
    602
    113
    second the visqueen sheet then fit on top if your levels are fine, especially if using fibre board underlay
     
  10. Rugmunching

    Rugmunching Well-Known Member

    3,679
    630
    113
    Make sure you look into exactly what you are covering the tiles with. Dont just throw the cheap B&Q stuff over it and think thats it. Get masked/overall'd up etc and take the tiles up. Bet they will fly up. Prime (NOT pva) then decent latex = job done. Dont rush because its the weekend and you want it done, get the right product first. Please dont just mix a bag of B&Q's super duper water base screed and think thats it. Seen it so many times where the screed has blown and needed scraping up and starting again!
     
  11. J d clarkson flooring

    J d clarkson flooring Well-Known Member

    254
    50
    28
    Only if the primer is moisture tolerant..... If it isn't it will also blow the screed. I'd recommend Ardex n/a if you wish to latex over or if you use any check it is suitable for floors with humidity over 75% as spacey says..... I'm afraid the vast majority of diy products are not up to the job in the hands of diy people.....:: I've lifted far too many failed floors recently at the cost of thousands
     
  12. J d clarkson flooring

    J d clarkson flooring Well-Known Member

    254
    50
    28
    Also have you considered a underlay with a built in dpm for laminate such as woodbloc
     
  13. Spacey

    Spacey Super Moderator Staff Member

    6,516
    1,878
    113
    Which Primers are moisture tolerant?
     
  14. dazlight

    dazlight Super Moderator

    6,864
    1,620
    113
    Epoxy


    On tapatalk HD
     
  15. Spacey

    Spacey Super Moderator Staff Member

    6,516
    1,878
    113
    I wasn't asking you :p
     
  16. Rugmunching

    Rugmunching Well-Known Member

    3,679
    630
    113
    I was referring to people putting down cheap screed WITHOUT a primer!
     
  17. J d clarkson flooring

    J d clarkson flooring Well-Known Member

    254
    50
    28
    Eurocol primer can be used under a dpm along with ultra new multi purpose primer
     
  18. Spacey

    Spacey Super Moderator Staff Member

    6,516
    1,878
    113
    So If I mix something like P51 or 360 with water say 4-1 ratio Can I use that under a dpm ?
     
  19. J d clarkson flooring

    J d clarkson flooring Well-Known Member

    254
    50
    28
    Well p51 is Ardex and I use n/a which if going under a dpm doesn't always need priming.... I'd check with the manufacturer on what installation method they recommend, not sure if p51 is moisture tolerant, last job I did Ardex advised a slurry mix of latex prior to screeding as a way to prevent pin holes and it worked great. Last job in level it 2 they said watered down primer as was indeed suitable under a dpm on new concrete floor and for eurocol the rep visits site and gives me a written advice spec if needed. There primer I use has been great on anhydride as well, once primed you need a kango drill to get the final coat off it grabs that well....... I detect a hint of sarcasm but not out for arguing only offering advice on what I know or have been told and has worked
     

Share This Page